Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752201AbZJQOzG (ORCPT ); Sat, 17 Oct 2009 10:55:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751984AbZJQOzG (ORCPT ); Sat, 17 Oct 2009 10:55:06 -0400 Received: from sh.osrg.net ([192.16.179.4]:47297 "EHLO sh.osrg.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212AbZJQOzD convert rfc822-to-8bit (ORCPT ); Sat, 17 Oct 2009 10:55:03 -0400 Date: Sat, 17 Oct 2009 23:51:32 +0900 To: akinobu.mita@gmail.com Cc: fujita.tomonori@lab.ntt.co.jp, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, davem@davemloft.net, sparclinux@vger.kernel.org, benh@kernel.crashing.org, paulus@samba.org, linuxppc-dev@ozlabs.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, gregkh@suse.de, LW@karo-electronics.de, linux-usb@vger.kernel.org, rolandd@cisco.com, yevgenyp@mellanox.co.il, netdev@vger.kernel.org, tony.luck@intel.com, fenghua.yu@intel.com, linux-ia64@vger.kernel.org, linux-altix@sgi.com Subject: Re: [PATCH 2/8] bitmap: Introduce bitmap_set, bitmap_clear, bitmap_find_next_zero_area From: FUJITA Tomonori In-Reply-To: <961aa3350910170743n4c9947d1ka0bd31aa1c7b9917@mail.gmail.com> References: <20091013091017.GA18431@localhost.localdomain> <20091017224028V.fujita.tomonori@lab.ntt.co.jp> <961aa3350910170743n4c9947d1ka0bd31aa1c7b9917@mail.gmail.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT Message-Id: <20091017235117U.fujita.tomonori@lab.ntt.co.jp> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.0 (sh.osrg.net [192.16.179.4]); Sat, 17 Oct 2009 23:51:34 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1982 Lines: 57 On Sat, 17 Oct 2009 23:43:56 +0900 Akinobu Mita wrote: > 2009/10/17 FUJITA Tomonori : > > On Tue, 13 Oct 2009 18:10:17 +0900 > > Akinobu Mita wrote: > > > >> My user space testing exposed off-by-one error find_next_zero_area > >> in iommu-helper. Some zero area cannot be found by this bug. > >> > >> Subject: [PATCH] Fix off-by-one error in find_next_zero_area > >> > >> Signed-off-by: Akinobu Mita > >> --- > >> ?lib/iommu-helper.c | ? ?2 +- > >> ?1 files changed, 1 insertions(+), 1 deletions(-) > >> > >> diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c > >> index 75dbda0..afc58bc 100644 > >> --- a/lib/iommu-helper.c > >> +++ b/lib/iommu-helper.c > >> @@ -19,7 +19,7 @@ again: > >> ? ? ? index = (index + align_mask) & ~align_mask; > >> > >> ? ? ? end = index + nr; > >> - ? ? if (end >= size) > >> + ? ? if (end > size) > > > > I think that this is intentional; the last byte of the limit doesn't > > work. > > It looks ok to me. Without above change, find_next_zero_area cannot > find a 64 bits zeroed area in next sample code. I meant that we don't want to find such area for IOMMUs (IIRC, it code came from POWER IOMMU). > unsigned long offset; > > DECLARE_BITMAP(map, 64); > > bitmap_clear(map, 0, 64); > offset = find_next_zero_area(map, 64, 0, 64, 0); > if (offset >= 64) > printf("not found\n"); > else > printf("found\n"); > -- > To unsubscribe from this list: send the line "unsubscribe linux-ia64" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/